Technical Savvy Spurs Rocketing Grain Yields

TONGWEI County in central Gansu Province has a low grain output, taking into account its per capita 5.7 mu (1 mu=0.0667 ha.) of arable land and 400,000 strong labor force, especially when compared to that of southern and eastern China. Jiangxi Province in southeastern China, for example, has just one mu per capita of farmland, but yields grain sufficient to export to other provinces. After a tour of Tongwei, the reasons for its scanty harvests become apparent.

Our county is located on Northwest China’s loess plateau, with its tracery of ravines and gullies. Its annual rainfall is just 380 mm, while annual evaporation exceeds 1,500 mm. The prevalence of barren ravines and gullies makes it impossible to irrigate any more than three percent of farmland.

After graduating from Lintao Agricultural College in 1983, I was assigned to Tongwei’s agro-technical station. The household responsibility system had then not long been in force, and farmers were keen to cultivate grain on their contracted farmland. The county’s barren soil, however, made it impossible to achieve even a 100 kg per-mu wheat yield. In times of drought farmers would suffer a total crop failure. To avoid hunger, local residents often had no alternative but to rely on government relief.

Duan Rangquan(first left) explains new farming techniques to local farmers.

 

In 1990, I was appointed deputy township head in the county in charge of promoting agricultural technologies. In the absence of technical support progress had been slow, and the average output of intensively cultivated wheat fields had risen to only 150 kg per mu. Consequently many farmers in the prime of their working lives chose to leave their hometown and find work in southern China’s burgeoning manufacturing sector. Tongwei, one of China’s least developed regions, more or less depended on its migrants’ remittance to support its 450,000 population.

Tongwei has no industrial base. Persistent drought has made the issue of how to improve dry farming agro-technologies and promote farmers’ income a top county government priority. Upon my appointment in 1998 as director of the country’s agro-technical center, I and my team of technicians guided farmers in cultivating water-efficient crops, and applied fertilization techniques specific to dry farming. The results, however, were disappointing.

The plight of arid areas like ours prompted technicians from the Gansu Academy of Agricultural Sciences and Yuzhong County’s agro-technical center to pool their resources from 2003 to 2004 on formulating a dry farming technique. They came up with a method that plants seeds in alternating broad and narrow furrows that are then covered with agricultural film. In 2005, we applied this new technique to corn planting on pilot areas of farmland.

The four main advantages of this technique soon became apparent. The first is that of water preservation; the agricultural film surrounding the soil retains water within it and prevents evaporation. Second is heat insulation; seeds sown in the film-mulched furrow thrive on the 2-3oC warmer microclimate created within it, which once they germinate also protects them from frost. Third is water collection. Corn grown in the locality must generally survive on what is locally known as the 5 mm “useless rainfall,” which does little more than dampen the topsoil and evaporates soon after. The new technique enables rainwater to collect in and penetrate through the furrow to the roots of each seedling. Finally, the film protects crops from weeds and pests.

Farmers in our county soon began to refer to corn cultivated in this way as “iron crops” resistant to both drought and frost.

The encouraging results of our pilot farming project led in 2006 to the county’s application of this new technique to 17,300-mu of corn fields. That year saw a bumper 600 kg per mu harvest. This successful result gave local farmers incentive to learn the latest agricultural techniques and farming methods.

Taking into consideration the fact that autumn in our county is when rainfall is highest, we started an experiment that entailed swathing farmland in film at the start of the next season so as to preserve the level of moisture in the soil at maximum level and avoid its evaporation during the long, arid winter. Rainwater preserved in autumn, therefore, could then be used to nurture seeds in spring when they need it most. These new technical innovations based on local conditions effectively resisted drought and increased output.

Encouraged by the success of their practical experiments, the county’s agro-technicians applied the full-film-coverage technique to multiple crops, such as garlic. They found that the use of black film on potato plantations was even more effective in raising the temperature and curbing weed growth.

In the years since, our county has extensively promoted the autumn full-film-coverage farming method, applying it to 145,000 mu of farmland in 2007, to 560,000 mu in 2009, and to one million mu in 2011. Tongwei has now completely adjusted its crop composition through broad application of the full-film-coverage technique, and by planting quality crops suited to local conditions that are capable of high yields. Corn, however, is still our main point of focus.

That Tongwei County had rid itself of the scourge of food shortages became official in 2011, when the Ministry of Agriculture granted it an award in recognition of its advances in grain production.

The full-film-coverage technique is now used in our county to cultivate more than one million mu of corn, 400,000 mu of potatoes and 300,000 mu of wheat. There are also 300,000 mu of minor cereals, oil-bearing crops, fruits and vegetables. Grain surpluses have moreover prompted breakthrough development in Tongwei’s animal husbandry and food processing industries. A number of enterprising farmers have set up cornstarch factories.

I believe that developing animal husbandry by exploiting grain surpluses is a sure way of enriching local farmers. Wang Gaisheng was one of the first to take part in the pilot corn plantation. In 2006, when he was 41, Wang gave up doing casual work in the city to return to his hometown, where he and his wife planted 35 mu of corn. This year, in addition to cultivating 55 mu of corn, Wang also raised 30 cattle that feed on the cornstalks left in his fields, and whose dung is put to use as the organic fertilizer we recommend for corn plantation.

Nowadays, Wang earns an annual RMB 1,000 per mu of corn. He also sells calves as oxen 9-10 months after their birth, each at a profit of RMB 1,500. By combining crop plantation with livestock breeding, Wang has developed a circular economy and shown local farmers how to get rich.